RMS suggested rejecting patches from non-registered users, for both GNU and non-GNU projects, because the FSF legal team recommends against accepting patches from anonymous users. While non-registered users may authenticate their patches by other means (GPG...), this is considered as a first step against anonymous patches.

This may have affected your project, if you use the sitewide default parameters. If needed, you can override this setting for your project using the "Main->Set Permissions" menu from your project page.